Many processes have been developed to remove the bitter tasting and smelling portions of fruit and vegetable juices and to produce a juice of attractive fresh flavor and appearance which contains both liquid and pulp or pomace particles in a form which will not separate upon standing and which can be held in a fresh condition for a reasonable period either in canned, frozen or chilled condition.
In several of such processes the pulp is separated from the liquid, each treated separately, and recombined. Additional steps taught by this prior art include the following:
A. removing the oxygen from the pulp as in Harwell, U.S. Pat. No. 3,301,685; PA1 B. replacing the bitter pulp with good pulp or washing the bitter pulp with water as in Sperti, U.S. Pat. No. 3,385,711; PA1 C. heating only the pulp and not the juice in processing as in Lund, U.S. Pat. No. 3,053,668; PA1 D. heating the homogenized pulp in an open kettle as in Harrell, U.S. Pat. No. 3,118,170; or PA1 E. freezing the pulp and its enzymes separately from the juice and then combining with the juice so as to separate the enzymes from the juice until thawed for use as in Brown et al, U.S. Pat. No. 3,278,315.
In processes employed in recent years to commercially prepare fresh juice from papayas, water is added to papaya meat, sugar, salt, citric acid and ascorbic acid. The mixture is then stirred and placed in containers to be held at room temperature or chilled. The product retains a bitter smell adversely affecting the taste. If not thoroughly stirred, it has a tendency to become lumpy and spoil. Papaya juice as prepared in this method, when left standing either at room temperature or chilled, separates, with the water rising to the top and thus is not attractive in appearance if bottled in transparent or translucent bottles. When in this condition it must be shaken before use.
In U.S. Pat. No. 2,178,593, Matoush describes the manufacture of a stable papaya juice product which incorporates with fluid from the pulp and some pulp, a liquid made from the papaya seeds from the papayas used for the product mixed with lime juice. Following the teaching of this patent, applicant has manufactured such a product, finding as evidence of being a stable product that separation does not occur within a few hours following its manufacture. However, this product had a mustard color instead of the typical papaya bright yellow color and instead of a true papaya taste, a bitter, unpleasant, slightly papaya flavor with a faint taste of lime.
According to James H. Moy, Associate Professor of the Food Science Laboratory of the University of Hawaii, the combination of the seeds and the acid of the lime juice retards bacteria growth and stabilizes the product. The papaya seeds contain benzylglucosinolate. This compound makes isophiocyanate. This compound is beneficial in the seed as it retards growth of bacteria in the papaya. This compound also makes a second product, benzylcynate which can be toxic to humans.